Hot and force blast cupola



3 SheetsSheet .1.

(No Model.)

M. HAMM. v HOT AND FORGE BLAST GUPOLA.

No. 354,899. Patented Dec. 28, 1886 (No Model) 3 Sheetk-Shefl. 2.' M. HAMM.

HOT AND FORGE BLAST CUPOLA' No. 354,899. Patented Dan. 28, 1886.

liiiii ll l'll (No Model.) w 3 Sheets-8heet 3. M. HAMM.

HOT AND FORGE BLAST GUPOLA.

Patented D60. 28. 1888.

M n A ML U .7 8

supply of superheated air.

UNITED STATES MARK HAMM, OF STOCKTON, CALIFORNIA.

HOT AND FORCE BLAST CUPOLA.

SPECIFICATION forming part of Letters Patent No. 354,899, dated December 28, 1886.

' 7 Application filed November 12, 1885. Serial No. 182,543. (No model.) I

To all whom it may concern.-

Be it known that I, MARK HAMM, a citizen of the United States, residing at Stockton, in the county of San Joaquin and State of California, have invented certain new and. useful Improvementsin Hot and ForceBlast Cupolas, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention has for its object improve ments in means or apparatus employed in the manufacture of steel; and it consists in the arrangement and combination of parts, which will be more fully described hereinafter.

That my said invention may be clearly understood and readily carried into effect, 1 will proceed, aided by the accompanying drawings, fully to describe the same.

In the drawings, Figure l is an elevation showing the main features of my invention, one of the cupolas and the superheated-air chamber being in vertical section. Fig 2 is a section of the superheated-air chamber. Fig. 3 is an elevation of the converter through line :0 m, Fig. 1. Fig. 4 is a section of the superheated air-chamber and one of the cupolas, through line a m of Fig. 1, and showing a top view of the converter. Figs. 2, 3, and 4 are on a larger scale than is Fig 1. Fig.5 is a top view of shell h. Fig. 6 is a vertical section of the same.

In all the figures like parts are marked with similar letters of reference.

In employing my invention I preferably erect a platform, A supported upon suitable pillars, A. Upon this platform I place at each side a cupola-furnace, both of the same construction, but which, for convenience, I separately designate-A being the left-hand cupola and IV the right-hand cupola. These cupolas are constructed of plates of boiler-iron riveted together, having their insides lined with firebrick and being provided with removable tops D and with blast-boxes, F, constructed as and for the purposes as will be hereinafter shown. Between these cupolas I place a chamber, I, for the purpose of making therein a This chamber contains a series of elbow'pipes, L, eight in number, their sixteenfeet being fixed to horizontal step sections of piping, M O P Q, suitably secured to the floor of the chamber I.

Between each of the feet of the pipes L in the sections M O P Q is a stop, which causes the air to course through the entire series of the pipes L continuously. The tops of the pipes L are secured together by an iron stud, L, which is perforated with suitable holes admitting set-screws, L, whose threaded ends screw into threads cut in the tops of the sections of the pipes L. This chamber I is connected to the cupolas A and W by elbow-shaped pipes E at its top on each side,through which the flame passes, as will ,be shown, from the tops of the.

cupolas A and \V into the upper part of the chamber I into direct contact with the pipes L. The superheated air from the chamber I is forced into the blast-boxes F of the cupolas A and Why means of the following-described connecting-pipes-wia, a pipe, Y, which has its final outlet in a converter, a, as will be shown, the flow into such converter being controlled by a valve, K, is connected with the step pipe-section M. Into this pipe Y is fixed a vertical elbow-pipe, N, the upper end of which is connected with a horizontal pipe, J, which extends across the chamber I and empties at its respective endsinto the blast-boxes F of the cupolas, the flow into which is controlled by valves J, (only one of which is shown in the drawings.)

The blast-boxes F. are of the following construction: The cupolas are preferably-twelve feet high. About two feet from their base they are enlarged about twelve inches horizon tally for aspace of about teninches vertically. Inside of this enlargement is a deflector, U, riveted to the side of the cupola, and having secured to it a wedge-shaped plate, V, to equal-v ize the flow of the air beneath the lower edge of the deflector U. The superheated air from the pipe J enters the blast-box F, and evenly flows by means of the deflector U and equalizer V beneath the edges of the former, and enters the cupola through inlets h, formed by a hollow cast-iron flange, h, hub-shaped, about the circumference of the shell of the cupola, the lower edge of which is curved upwardly, so that the air may strike evenly and at the center of the cupola.

The chamber I is provided with a damper consisting of a stack, S, opening at its bot-tom into the chamber, and having a cap or top, T, at its apex, operated by a lever.

The tops of the cupolas are open, having covers or caps D suspended by chains from davits O, and reached by the operator from a platform, B, secured to the sides of the cupolas.

The cupolas at their bottoms are supplied with atap, H, for drawing oil the molten metal; also, with an eyeglass, G, for observing the condition of the metal under process.

The pipe Y, heretofore referred to, is connected with a converter, a, mounted upon standards d, and having its position controlled by a ratchctgear, e, engaging with a ratchet havinga handle, f,with asquare end admitting a wrench, so as to change the converter ver tically for the purpose of cleaning it out. The pipe Y is connected to the section-pipe i of the converter by a coupling,'j, the end of the pipe ihaving male threads engaging with the female threads of the coupling. It is also supplied with a tap, g, for drawing off the metal for the purpose of running it into bars.

In the event the usual method of providing heat, as will be described, is not found suflicient, a furnace of any ordinary construction may be built at the rear of the chamber I, and an auxiliary fire therein provided, increasing the heating properties of the chamber I.

Having described the construction of my hot-blast cupola,hot-airchamberand their connections, and internal and external machinery, I will now describe the method of operating the same for the purpose of producing the best quality of cast-steel and of pig-iron at a minimum cost.

I first place suitable igniting material in the bottom of each cupola and ignite the same through the tap-hole. When such material is afiame I fill each cupola with a suitable quantity of coke, removing the caps D forsuchpurpose. When the coke is at a white heat I place in the cupola A a charge of pig-iron or other mixture, and in the cupola W a charge of raw iron ore. Air is then admitted into I pipesL of the chamber I, being forced through the inlet-pipe O. The flames from the cupolas enter the chamber I through the pipes E and heat the pipes L to a cherry-red, heating the air flowing through them to a high degree. It then flows through pipeR into the cupolas, and by means of the deflectors U and equalizers V flows evenly through the inlets h and comes in contact with the material itself at a center, by reason of the curved lower edge of the shell h. This curved lower edge of the shell h prevents the superheated air from making contact with the brick lining of the cupola,

. thereby saving it from burning out as soon as it does in other styles of furnaces. The damper T controls the degree and quantity of hot air in the chamber I. When the material in the cupola A is sufiiciently melted, the entire blast is concentrated (by turning off the valves J at the ends'of pipe R, leading into cupola A) upon the ore in cupola W, which, when sufficiently melted, is tapped and drawn off and molded into pigs of cast-iron. When this is accomplished, the 'metal'in the cupola A is tapped and run off into the converter a, and the entire hot-air blast from the chamber I is concentrated upon it, the valves J of pipe B being closed for the purpose and the valve K of pipe Y being opened, and the connection of pipes Y and i being made by the 7 5 coupling The molten metalin the converter a is freed by the blast from all impuritiessuch as carbon and phosphorusand aproduct left, consisting of the most refined quality of steel, fit to be rolled into bars of any kind.

It will readily be seen that I make a most economical disposal of the fuel I employ, and produce a maximum result at aminimumcost.

I am aware that it is not new to employ, in connection with a cupola-furnace, a chamber into which the products of combustion pass, and in which are arranged pipes which are heated by the products of combustion, and in which the air passing through the pipes is heated and then fed to the furnace, and this I disclaim. My invention difi'ers from furnaces of this kind in a platform upon which the eupolas A WV and chamber I are placed, the two cupolas being connected together by the pipe R, and the air-supply pipes being passed 5 through the chamber and then connected toa converter in position under the platform. Each of the cupolas is provided with a blast'box provided with deflectors and equalizers and openings through which the hot blast enters the cupolas, the connecting-pipe B being made to pass through the chamber I and connected to the other pipes placed therein.

Having described my invention, what I claim as new is 1. The chamber I, provided with the series of vertical pipe-sections L, secured to the horizontal step sections M O P Q, suitably secured to the floor of the chamber I, and at their tops secured by the iron stud L and set-screws r [0 L, and having the pipe S and damper T, in combination with the cupola-furnaces A and W, being connected therewith by the upper pipes, E, and lower pipe, R, the pipe B being provided with suitable valves, each furnace 5 being provided with a blast-box, F, containing the deflector U, the equalizer V, and shell h, having the inlets h, and curved lower edge, all operating substantially as set forth and described.

2. In a blast apparatus, the combination, substantially as described, of the chamber I, containing the series of pipes M O P Q L, the connecting-pipes E E R, the cupola-furnaces A W, the discharging-pipe Y, the converter a, I 25 the platform A, and the pillars A.

3. The cupola-furnaces A W, provided with the blast-boxes F, containing the deflectors U, the equalizers V, and shell h, having the inlets h for the passage of the hot air into the furnaces, I30 in combination with the pipes E and R, the ends of the latter of which are adapted to discharge the hot air from the chamber I into the blast'boxes F, and the ends of the former of which are adapted to permit the flow 0f the In testimony whereof I affix my signature in flame from the furnaces into the chamber I, presence of two witnesses. the chamber I and furnaces A W being suitably 'monnted on platform A supported by 5 pillars A, said chamber Ibeing provided with Witnesses:

a pipe, Y, for conducting the blast into a con- ELIHU B. STOWE,

. verter, a, all substantially as set forth. JOSHUA B. WEBSTER.

MARK HAMM. 

